Air conditioning



Nov. 11, 1969 M. WARREN, JR

AIR CONDITIONING Original Filed May 4, 1965 FIG? FEGZ

20 m 2 MW.

ATTORNEYS United States Patent Office 3,477,497 AIR CONDITIONING Robert M. Warren, Jr., Red Bank, N.J., assignor to Buensod-Stacey Corporation, New York, N.Y., a corporation oi Ohio Original application May 4, 1965, Ser. No. 453,034, now Patent No. 3,367,407, dated Feb. 6, 1968. Divided and this application Feb. 1, 1968, Ser. No. 702,390

Int. Cl. F25b 29/00; B60h 1/00; B61d 29/00 U.S. Cl. 165-22 4 Claims ABSTRACT OF THE DISCLOSURE A device having a housing with primary and recirculated air inlets, there being a fan in the housing and a heat exchanger through which the recirculated air passes, the primary air inlet being connected to the side of the housing.

The present invention relates to air conditioning systems, and particularly to a fan coil type of air conditioning unit.

This application is a division of application Ser. No. 453,034, filed May 4, 1965, and now Patent No. 3,367,- 407, granted Feb. 6, 1968.

It is known to supply conditioned primary air to a room or zone to be controlled through a distributing unit within the room or zone, the distributing unit being supplied with said primary air from a central source. It is also known to employ an air heating or cooling heat exchanger element within the room or zone adjacent to or in the distributing unit. Such is arranged so that secondary or recirculated air from the room is induced by the flow of primary air through the distributing unit to flow over the heating or cooling heat exchanger unit.

In prior arrangements, the primary air has been relatively constant in volume and temperature, while the room or zone control has been through the unit heat exchanger by varying fluid flow or by air bypass. This usually necessitates some degree of zoning and change-over of control seasonally and even hourly.

One of the objects of the present invention is to provide an air conditioning system having the advantages of a dual duct system in which zone air is recirculated, to simplify control requirements and to provide inherent flexibility. Thus, the dual duct primary system can provide complete control of all spaces with reduced equipment capacity for most of the year. During peak load periods, the secondary circulation through the heat exchanger can boost capacity, especially cooling capacity, to the required amount with control remaining in the double duct system.

In one aspect of the invention, a distributing device or box is provided for each room or zone. Warm and cold primary air issupplied from the usual dual duct central conditioning means through ducts to a control valve or damper means for proportioning the warm and cold air to provide the desired zone temperature. A volume regulator receives the mixed proportioned air and discharges it at substantially constant volume into the primary air inlet of the distributing device.

In another aspect of the invention, a fan may be provided in the distributing device in position to receive the proportioned air from the constant volume regulator and to force it out of the distributing device into the room or zone being conditioned.

In still another aspect of the invention, a grille may be located in the distributing device for admitting room or zone air to cause its recirculation and mixing with the primary air from the constant volume regulator.

In still another aspect of the invention, a heat exchanger 3,477,497 Patented Nov. 11, 1969 means, over which the recirculated air passes as it enters the distributing device, may be fed with heating or cooling fluid in accordance with the season.

By the use of the present invention, valves and other troublesome liquid control means, at the units, are eliminated. Where a predetermined small amount of fresh air is required or when air from other zones cannot be recirculated, such as in hospitals, the present system provides a simple manner in which to accomplish the same. The system is particularly efiicacious where the dual duct system is of the medium or high pressure type.

The above, other objects and novel features of the invention will become apparent from the following specification and accompanying drawings which are merely exemplary.

In the drawings:

FIG. 1 is a view of an air conditioning unit to which the principles of the invention have been applied and which is the subject matter of said parent application Ser. No. 453,034; and

FIG. 2 is a modified form of the apparatus shown in FIG. 1.

The invention will be described in conjunction with a distributing unit in a zone or room to be conditioned, it being understood that any number of distributing units or devices can be used as needed in a zone or in a plurality of Zones.

Referring to the drawings and particularly to FIG. 1, the principles of the invention are shown as applied to an air conditioning unit including a housing 10 having a grille 11 extending along substantially the entire length of the top surface of housing 10. A funnel-shaped plenum 12 may be fastened to the inside surface of the top of housing 10, and it may have a reduced section that is connected to the outlet of a conventional motor operated fan 13.

The primary air is supplied to plenum 12 through passage 14 leading from mixing chamber 15. Mixing chamber 15 may be adjacent the housing 10, such as under the floor, or may be within the housing. Warm and cold air can be supplied from a central conditioning unit through ducts 16 and 17 as is known in a dual duct system to which this invention particularly applies. A valve or damper between ducts 16 and 17 may be controlled by a valve operator 18 that can be operated by a thermostat 19 to proportion or mix the warm and cold :air as needed. The thermostat control can be of any suitable type, such as pneumatic or electrical. A suitable damper arrangement is illustrated in U.S. Patent No. 2,720,151. Preferably, a volume regulator 20 is employed to keep a constant volume of air supplied to passage 14. One type of volume regulator, using flexible curtain means, is seen in U.S. Patent No. 2,890,716.

Housing 10 may include a secondary or recirculated air grille or aperture 21 in one side wall thereof. Adjacent the recirculated air aperture 21 and at right angles thereto is located heat exchanger 22 extending substantially over the entire inside area of housing 10. Heat exchanger 22 may be of the conventional finned type with heat exchange medium or liquid lines 23, 24 for feeding liquid or fluid therethrough. The lines 23, 24- may be part of a closed system through which a constant volume or quantity of heat exchange fluid or liquid may be continuously passed by pump 25 from reservoir or supply means 26. Seasonally, the fluid flowing through lines 23, 24 may be hot or cold, as desired, in accordance with whether reservoir 26 is heated or cooled. The heat exchange fluid preferably flows at a substantially constant volume and at a selected temperature through the exchanger.

The primary air is mixed and brought to the required temperature as called for by zone thermostat 19. Operation of fan 13 draws a constant volume of primary air from mixing chamber 15 and recirculating air from the room or zone through aperture or grille 21. The recirculated air and primary air mix and pass upwardly through the heat exchanger 22 which imparts heating or cooling thereto depending upon the season of the year.

The volume regulator 20 keeps the volume of primary air constant. Thus, the temperature of the zone is governed by controlling the temperature of the mixed primary air by properly proportioning warm and cold air from the dual duct system without using any control elements to control flow of heat exchange fluid through heat exchanger 22.

In the form shown in FIG. 2, to which this divisional application is directed, the mixing chamber is shown mounted on the side of housing 10, admitting primary air to housing above the exchanger 22. In this embodiment, operation of the fan 13 draws a constant volume of total air into housing 10. The volume regulator 20 controls the volume of primary air which is less than the total fan cubic feet per minute. The primary air is mixed above heat exchanger 22 with recirculated air that is drawn through grille 21 and which latter air is subjected to heating or cooling by heat exchanger 22, depending upon the prevailing conditions.

Although the various features of the improved air conditioning unit have been shown and described in detail to fully disclosed two embodiments of the invention, it will be evident that changes may be made in such details and certain features may be used without others without departing from the principles of the invention.

What is claimed is:

1. In an air conditioning system, the combination comprising an air distributing housing having an air distributing grille at its top; recirculated zone air inlet means in a side wall of said housing; heat exchanger means through which said recirculated air can at all times pass; primary air supply means connected to the side wall of said housing above said heat exchanger means, primary air passing therethrough; a fan within said housing having its outlet connected to said air distributing grille; means for supplying heat exchange medium to said heat exchanger means; and means for varying the condition of said primary air in response to zone temperature.

2. A system as in claim 1 and including means for varying the condition of said primary air; and constant volume control means in the path of said primary air to maintain the volume thereof constant.

3. A system as in claim 1 and including ineans for supplying warm and cold air to said primary air supply means; and means for varying the proportion of warm and cold air in response to zone temperature.

4. A system as in claim 1 and including means for supplying warm and cold air to said primary air supply means; means for varying the proportion of warm and cold air in response to zone temperature; and constant volume control means in the path of said primary air to maintain the volume thereof constant.

References Cited UNITED STATES PATENTS 8/1943 Otis 122 9/1957 Cowrabi 16522 

